Call centers use predictive dialers to increase the amount of time agents spend on the phones engaging with customers. Predictive dialers are telecommunication systems employing an automatic call distributor having a multiport switch controlled by a central control processing unit in conjunction with a main memory for selectively interconnecting outbound telephone calls answered by customers with agents within the network. Predictive dialers dial a list of telephone numbers and connect answered calls to agents. Predictive dialers use statistical algorithms to minimize the time that agents spend waiting between conversations, while minimizing the occurrence of someone answering when no agent is available. A variety of features and upgrades have been added to these systems to maximize the efficiency of the call center. Prior to predictive dialers, agents spoke to customers about 66 percent of time, while the rest of the time was spent dialing numbers and waiting for responses. Predictive dialers handle dialing tasks, thereby allowing agents to speak to customers as much as 95 percent of the time. Call centers wish to continue to improve performance by reducing further an agent's idle time. One way in which call centers are capable of reducing an agent's idle time is by interpreting data faster than they have before, or by interpreting data using different methods, which allow call centers to be proactive, rather than reactive.
One example of a time reducing feature is answering machine detection. It works by determining the difference between a pre-recorded voice reproduced by an answering machine, and a live voice. There are several methods used to identify pre-recorded voice and live audio. The primary method used by call centers is by employing devices that have separate timers to track pauses in audio. A large pause after the initial greeting word may indicate live voice. A shorter pause after the initial greeting word may indicate the prerecorded voice asking the caller to leave a message. In known answering machine detection systems, a first timer, sometimes called the greeting timer, is triggered upon detection of the initial audio signal. A second timer, called the pause timer, is triggered upon detection of an absence of an audio signal and runs for a predetermined time after the initial audio signal is detected. If there is no elongated pause, or the pause time from the initial voice detection is less than the preselected pause time period, then the pause timer does not expire, and the greeting timer will expire first. If the greeting timer expires before the pause timer, then the length of a pause has not met the preselected period of time, and thus an answering machine is determined to be present.
A timer-based detection system may not properly characterize an answering machine or live voice causing at least two undesirable outcomes. The first undesirable outcome occurs when the detection system mistakes live-voice from a customer as an answering machine and terminates the call, resulting in the customer receiving a silent or abandoned call. Call centers may have limits on the acceptable number or percentage of outbound silent calls based on call regulations, and call centers may be penalized or fined when they exceed those limits.
The second undesirable result occurs when the detection system mistakes an answering machine for live-voice. This occurs when the detection system encounters a recorded message with a long initial pause and, rather than dispose of the call, instead distributes the call to an agent, thereby wasting the agent's time and decreasing the accuracy of the call center.